ZombieCon, an annual October event in Fort Myers, Florida, became a scene of chaos and terror on Saturday after a person or persons opened fire into a crowd of about 20,000 people.

The event, which took place in the middle of downtown Fort Myers, was almost over for the day when the bullets began to fly, killing one man and wounding four others. The victim, 20-year old Expavious Tyrell Taylor, died at the scene. The suspect or suspects remains at large, with a massive manhunt underway on Sunday. Police are now asking for the help of attendees, saying that someone might have captured something important in a picture or video.

“There were a lot of witnesses down here, there were a lot of people taking pictures, videos with their cellphone. Anything that could help with this investigation would be greatly appreciated,” said Lt. Victor Medico.

Several eyewitnesses say they weren’t sure at first if the gunfire was real or part of a stunt for the event; of notable concern is the fact that many attendees were dressed up in costumes that included fake weapons.

“I was right here. A mass of people ran screaming and trying to get in the shop…There are people dressed up and some walking around with guns. How do you know they aren’t real? Any event I come to, this will be in the back of my mind,” said local business owner Jill Stancel.

Investigators are still reviewing surveillance footage from local businesses for any clues as to the shooters’ identity; it’s the second act of gun violence in that area in a week. However, no cameras are available in the downtown area. Mayor Randall P. Henderson Jr. says he is working hard to get them installed.

“Sadly, we’re moving in that direction. We need to be way more vigilant to keep citizens safe,” Henderson said.